1. Field of the Invention
This invention relates to shift mechanisms and in particular it relates to a multiple position shift mechanism for shifting between various positions of two-wheel drive and four-wheel drive of a four-wheel drive vehicle.
2. Background Information
Four wheel drive vehicles are commonplace on the roadways today. They provide added traction when needed under adverse weather conditions where a user may encounter mud, snow, and ice. They also provide mobility in off-the-road travels where soft terrain is encountered
When traveling on the normal hard surface of the roadways the vehicle is operated in the two-wheel drive mode. The vehicle may be shifted to conventional four-wheel drive when encountering ice or snow on the roadway and then to low range four-wheel drive when driven off the road where the terrain demands both four-wheel drive and low range power. A neutral position is also desirable for towing the vehicle.
Having the ability to change or shift between the different positions as desired requires a shift mechanism to shift the gears within the vehicle's transfer case.
Shifting mechanisms in prior devices have not provided a secure neutral position or the desired operator feel when positioned in neutral. Also, the multiplicity of parts and the complexity of manufacture makes prior devices expensive to manufacture and assemble. When repairs are required, it is a major task to disassemble, replace worn or broken parts and reassemble.